using System;
using System.IO;

/*
 * This file is part of the iText project.
 * Copyright (c) 1998-2009 1T3XT BVBA
 * Authors: Bruno Lowagie, Paulo Soares, et al.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License version 3
 * as published by the Free Software Foundation with the addition of the
 * following permission added to Section 15 as permitted in Section 7(a):
 * FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY 1T3XT,
 * 1T3XT DISCLAIMS THE WARRANTY OF NON INFRINGEMENT OF THIRD PARTY RIGHTS.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU Affero General Public License for more details.
 * You should have received a copy of the GNU Affero General Public License
 * along with this program; if not, see http://www.gnu.org/licenses or write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA, 02110-1301 USA, or download the license from the following URL:
 * http://itextpdf.com/terms-of-use/
 *
 * The interactive user interfaces in modified source and object code versions
 * of this program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU Affero General Public License.
 *
 * In accordance with Section 7(b) of the GNU Affero General Public License,
 * you must retain the producer line in every PDF that is created or manipulated
 * using iText.
 *
 * You can be released from the requirements of the license by purchasing
 * a commercial license. Buying such a license is mandatory as soon as you
 * develop commercial activities involving the iText software without
 * disclosing the source code of your own applications.
 * These activities include: offering paid services to customers as an ASP,
 * serving PDFs on the fly in a web application, shipping iText with a closed
 * source product.
 *
 * For more information, please contact iText Software Corp. at this
 * address: sales@itextpdf.com
 */
namespace iTextSharp.text.pdf {

    /** Implements PDF functions.
     *
     * @author Paulo Soares
     */
    public class PdfFunction {
    
        protected PdfWriter writer;
    
        protected PdfIndirectReference reference;
    
        protected PdfDictionary dictionary;
    
        /** Creates new PdfFunction */
        protected PdfFunction(PdfWriter writer) {
            this.writer = writer;
        }
    
        internal PdfIndirectReference Reference {
            get {
                if (reference == null) {
                    reference = writer.AddToBody(dictionary).IndirectReference;
                }
                return reference;
            }
        }
        
        public static PdfFunction Type0(PdfWriter writer, float[] domain, float[] range, int[] size,
            int bitsPerSample, int order, float[] encode, float[] decode, byte[] stream) {
            PdfFunction func = new PdfFunction(writer);
            func.dictionary = new PdfStream(stream);
            ((PdfStream)func.dictionary).FlateCompress(writer.CompressionLevel);
            func.dictionary.Put(PdfName.FUNCTIONTYPE, new PdfNumber(0));
            func.dictionary.Put(PdfName.DOMAIN, new PdfArray(domain));
            func.dictionary.Put(PdfName.RANGE, new PdfArray(range));
            func.dictionary.Put(PdfName.SIZE, new PdfArray(size));
            func.dictionary.Put(PdfName.BITSPERSAMPLE, new PdfNumber(bitsPerSample));
            if (order != 1)
                func.dictionary.Put(PdfName.ORDER, new PdfNumber(order));
            if (encode != null)
                func.dictionary.Put(PdfName.ENCODE, new PdfArray(encode));
            if (decode != null)
                func.dictionary.Put(PdfName.DECODE, new PdfArray(decode));
            return func;
        }

        public static PdfFunction Type2(PdfWriter writer, float[] domain, float[] range, float[] c0, float[] c1, float n) {
            PdfFunction func = new PdfFunction(writer);
            func.dictionary = new PdfDictionary();
            func.dictionary.Put(PdfName.FUNCTIONTYPE, new PdfNumber(2));
            func.dictionary.Put(PdfName.DOMAIN, new PdfArray(domain));
            if (range != null)
                func.dictionary.Put(PdfName.RANGE, new PdfArray(range));
            if (c0 != null)
                func.dictionary.Put(PdfName.C0, new PdfArray(c0));
            if (c1 != null)
                func.dictionary.Put(PdfName.C1, new PdfArray(c1));
            func.dictionary.Put(PdfName.N, new PdfNumber(n));
            return func;
        }

        public static PdfFunction Type3(PdfWriter writer, float[] domain, float[] range, PdfFunction[] functions, float[] bounds, float[] encode) {
            PdfFunction func = new PdfFunction(writer);
            func.dictionary = new PdfDictionary();
            func.dictionary.Put(PdfName.FUNCTIONTYPE, new PdfNumber(3));
            func.dictionary.Put(PdfName.DOMAIN, new PdfArray(domain));
            if (range != null)
                func.dictionary.Put(PdfName.RANGE, new PdfArray(range));
            PdfArray array = new PdfArray();
            for (int k = 0; k < functions.Length; ++k)
                array.Add(functions[k].Reference);
            func.dictionary.Put(PdfName.FUNCTIONS, array);
            func.dictionary.Put(PdfName.BOUNDS, new PdfArray(bounds));
            func.dictionary.Put(PdfName.ENCODE, new PdfArray(encode));
            return func;
        }
    
        public static PdfFunction Type4(PdfWriter writer, float[] domain, float[] range, string postscript) {
            byte[] b = new byte[postscript.Length];
                for (int k = 0; k < b.Length; ++k)
                    b[k] = (byte)postscript[k];
            PdfFunction func = new PdfFunction(writer);
            func.dictionary = new PdfStream(b);
            ((PdfStream)func.dictionary).FlateCompress(writer.CompressionLevel);
            func.dictionary.Put(PdfName.FUNCTIONTYPE, new PdfNumber(4));
            func.dictionary.Put(PdfName.DOMAIN, new PdfArray(domain));
            func.dictionary.Put(PdfName.RANGE, new PdfArray(range));
            return func;
        }
    }
}
